The candidate has developed a strategy for the genetic analysis of cognitive processes related to attention. Through an NRSA postdoctoral fellowship under the mentorship of Dr. Michael Posner, we have used the Attention Network Task (ANT), to systematically explore the genetic underpinnings of attention networks. Our method is systematic insofar as it first assesses the validity of executive attention measurements, then the reliability of the measurements, then the heritability using twin studies, then the effects of specific candidate genes using mixed population gene association studies, and finally the anatomical correlates of gene function using structural and functional MRI. The method is designed to progressively weed-out, candidate cognitive assays (where performance is not heritable) as well as candidate genes (that show no association with behavior) before making inferences on how such genes might influence specific cognitive processes in an imaging genetic (genetic variation vs. brain structure and activity) paradigm. Our prior work in adult subjects, which forms the foundation for this proposal, was built on data showing that measurements of executive attention using the ANT were reliable and heritable. A study of several dopaminergic genes that have been associated with developmental disabilities showed that the DRD4 and MAOA genes showed associations with efficiency of executive attention and that frontal midline regions including the ACC are especially influenced by variation in the MAOA and DRD4 genes. I propose to repeat this genetic &imaging study design using a child friendly version of the ANT in children, ages 6-10, an age when executive attention has just reached a plateau. Additional developmental candidate genes such as nuclear receptor related (NURR1) and synaptosomal associated protein (SNAP25) will also be examined given their critical role in the development of the dopamine system.